Prostaglandin, prostacyclin and thromboxane synthesis will be studied in mammalian cells growing in tissue culture. Emphasis will be placed upon determining the control factors which regulate the overall rate of production of these products of arachidonic acid metabolism. The distribution of products from 14C arachidonic acid supplied to the cells will be measured using a combination of thin layer, gas chromatographic and mass spectrometric procedures. The influence of cell transformation upon control of prostaglandin-thromboxane-prostacyclin production will be measured. The relationship of these control mechanisms to oncogenesis, the differential inhibition of the various products of cyclooxygenase activity by aspirin and other anti-inflammatory drugs and the relationship of increased prostaglandin production by co-carcinogens such as the phorbol diesters will be examined.